It is well known to provide mounting structures for video cameras to be installed in or near buildings to be protected by a video surveillance system. The mounting structures typically include a housing that is secured to the ceiling of the building or at another suitable location on the building. The housing contains a video camera, motors and other components which permit the camera to be moved by remote control through a range of motion, and electronics for receiving control signals and transmitting video signals generated by the camera. Frequently, a portion of the enclosure is in the shape of a dome and is formed of plastic which permits incident light to enter and be captured by the video camera. The assembly, including the housing, the camera and associated components, are together commonly referred to as a "dome", which takes its name from the dome-shaped portion of the housing.
After the initial installation of the dome, the need arises from time to time to remove the dome for purposes such as routine maintenance, repair or replacement. To that end, it is known to mount on the upper part of the dome a plurality of spring loaded rods which are releasably inserted into suitably shaped brackets secured to the ceiling or other support structure. A safety lanyard also is provided on the dome, and a free end of the lanyard is removably secured in another bracket mounted on the ceiling. Removal of the dome from the structure on which it is installed requires the individual assigned to perform the removal to be close enough to the dome so that the individual is able to reach by hand to disengage the spring-loaded bolts from the mounting brackets and to release the safety lanyard. It is common practice to install surveillance camera domes in high ceilings, or otherwise at a considerable distance from ground or floor level, both to provide satisfactory fields of view for the cameras and to deter unauthorized interference with the cameras. In such installations, removal of the camera entails climbing a considerable distance upwards on a ladder, or deploying suitable scaffolding, in order to approach the dome. Two hands are generally needed to manipulate the spring-loaded bolts so as to release the dome from the mounting brackets, and to release the safety lanyard while holding the dome, leaving the individual concerned to maintain his or her balance on the ladder without aid of hands.
It is also to be noted that dropping a dome during the removal process is likely to result in significant financial loss since domes are generally fragile and have a substantial replacement cost.
In light of the preceding discussion, it is not surprising that many operators of video surveillance systems call upon the supplier of the system to dispatch a trained employee to the operators' premises when removal of a dome is needed. The cost and inconvenience entailed by this practice is considerable, raising a need for a dome mounting system that facilitates removal and replacement of the domes.